1) Field of the Invention
The present invention refers to a tap for dispensing liquids from vessels, particularly vessels of the rigid type or of the so-called “bag-in-box” type. The following description will refer to the application of the inventive tap onto a rigid vessel, commonly used for containing water or similar liquids, but it is obvious that the inventive tap, with few adaptations (removal of air entering mouths and creation of a layout adapted to be placed on a fixing opening for this type of taps), can be used also for “bag-in-box” vessels or other types of vessels.
2) Background Art
In order to dispense water from rigid vessels, very few tap arrangements are known in the art, all characterized by a high number of parts, some of which, due to their nature, are also very costly: the end result is a highly costly tap, that cannot be realized in practice, since it heavily affects the final cost of the liquid-vessel-tap product, cost that is given by stamping and assembling steps.
The known taps are costly because, in applications with rigid vessels, to avoid having to drill the vessel itself so that air enters in it while liquid goes out of it, the tap had to be equipped with at least one air passage able to be actuated (namely able to be opened and closed) together with the liquid dispensing passage. However, all existing taps provide that the two above-mentioned passages are placed one above the other with respect to the liquid dispensing axis: this forces to provide the tap with a control member to be made of two pieces, in order to obtain seal and operation. And the external control piece (namely a sort of dome-shaped resilient push-button), to be realized separately from the control piston, is a very costly piece of resilient plastic material. In addition thereto, there are taps with air passage made of many parts that are opened by rotation (and not by squashing of a resilient membrane), and that have a seal of the cylindrical type—but they have various problems: for example, they have no automatic closure, namely their closure must be performed by the user, they have no warranty seal, etc.
Moreover, the known taps, once being assembled onto a vessel neck, cannot be oriented at will (since once arrived at the end of their thread, they are blocked in place and cannot be moved any more), and therefore require either to make the rear tap area (area with thread+body area+gasket, that allows a relative movement especially adapted to orient the body) of three pieces, in order to obtain seal, operation and orienting, or they require the user to suitably place the vessel to which the tap is connected in such a way as to correctly orient the tap, in order to allow tapping the liquid. Moreover, in case of a body made of a single piece and not three, like the previously described one, a particular thread geometry on the neck is required (it is necessary to adequately compute the thread start both of the vessel neck, and of the tap body in order to orient the tap at the end of its screwing) of the vessel in order to place the part immediately in its correct position.